Apparatus for stretching sheet glass



Feb. 6, 1923.

A R UWLEY l APPARATUS FOR STRETCH 1 Ns Swear GLASS 2 sHeETS sHeET i F l LED Nov k Feb. 6, 1923.

C, A R OWLEY APPARATUS Fore. SQETcmNo SHEET GLASS4 2 sHEETssHEET 2 FILED Nov INVENTOR WMM@ PatentedFeb. 6, 1923.

UNrT-ED STATES PATE 1,444,038 NATd OFFICE.

CLITFOD `A..B.0WLEY,' 0F TOLEDO, OBID, ASSIGNOB T0 THE' LIBBEY-OWENS SHEET oLAsscomrmY, or Torrano, omo, A CORPORATION `or omo.

Application and november i, 1920. serial m. 420,901.

Tofal'l 'whom it may concern .i

acltizen o f t e-United States, residing at Toledo, in the county of Lucas and StateofOhio, have invented new and useful Ini- -grjements in Apparatus for Stretching heet Glass, of which the following is a spcification.

i This invention relates to the art of draw- 10..

ing lass in sheet form from a molten mass of g ass, and is concerned more particularly ivit an apparatus for stretching the sheet laterally, while it is being drawn, to flatten the sarne and improve the quality of the `While the invention is adaptable to any form of sheet drawing apparatus, it is here shown as anA improvement or addition to the ap aratus disclosed in the patents to I. W. olburn, huesos, dared D c. 4, 1917, and 1,274,385, dated Aug. 6, `191 In this patented apparatus, a sheet of glass is -d'rawn upwardly from 'a bath of molten glass, bent' into a horizontal plane, rehealed, and then passes through a drawing mer-bib nism which gives the required longitudinal pull to claw the continuous sheet from its molten source, and at the same time flattens the reheated and softened sheet into its final form. The present invention so modifies this apparatus that the glass sheet is stretched laterally, while engaged by thc draviing mechanism, to further flatten the sheet', and remove The rcsultto be accompanied is the same waves and wrinkles.

as contemplated in the copending application of Seth B. Henshaw. Serial Number! In the present the edges ofthe sheet to pull the sheet longitudinally, are simultaneously moved laterally to stretch the sheet in width. lin this way, a steady and substantially uniform cn- .sion is applied in all directions over a considerable area oi 'the sheet, to draw out waves or corrugations and produce a smooth and Hat sheet.

The exact nature and objects of this inrention `fill become more apparent as the following detailed description of one approved form of apparatus for carrying out the invention proceeds,

Referring to the accompanying drawin l, is a vertical longitudinal section through a sheet drawing machine `of the Colburn type with the present invention applied thereto.' Y I Fig. 2 is ay vertical transverse section through the sheet drawing mechanism, substantially on the line 2 2 of Fig. 1.

Fig. 3` is a-par'tial plan view of the drawing mechanism vparts being cut away substantially on the line 3-3 of Fig. 2, and a portion ofthe draw-table being omitted be- Heath the draw-bars at the left-hand side of the ligure, for the sake of clearness.

Fig. 4 is an enlarged transverse section if one end of theiapparatus as shown in Fig. 5 is a-partial vertical section, substantially on the line 5-5 of Fig. 4. y

Referring first to Fi 1, the glass sheet 1f is drawn up from the ath of molten glass 2, in receptacle 3, between edge forming rollers 4, and coolers 5, then bent over cooled bending roller 6, and passed o' horizontally through the drawing mechanism and into the annealing leer" 7, all as shown and described more particularly in Patent 3o 1,248,809, above noted. After' leaving the bending roll (i, the sheet is reheated and softened by burners 8aud th'e temperature of tbe sheet and of the various parts of the apparatus isregulated by suitably ar- 35 ranged burners, some of which are illustrated by way of example at the various 'points 9. The mechanism for applying thc longitudinal draft, whereby the sheet is continuously pulled from the molten mass is substantially' o f the form set forth in ('olburn Patent 1,274,385, referred to above. It comprises a suitable carrier or draw-table 10, in the form of an endless fiexihle chain.

'ofclosely intermeshing links 11. The table 96 is of substantially the width of the sheet to be drawn. and is supported throughout its upper run by the stationary table 12. The flexible draw-table is carried at its ends` :1nd driven by, the Sprockets 13. and the 100 lower returnl run of the loop is supported by the idler roll 14. Above the sheet is arra nged an endless series of transverse dra vrbars 15, carried by sprocket chains 16, supported and driven by sprockets 17. These draw-bars 15 are usually U-shaped in crosssection, af'ndbear on the glass sheet adjacent their ends only; the drawing process forming the glass sheet withy thicker edge portions. If desired the draw-bars cpuld be ,L10

edgeportions of the glass sheet, gripping the sheet' between the draw'bars and drawvtable', which move synchronously thus ini- Vpartingy continuous longitudinal movement to the sheet. At the same time the reheated and softened-sheet is flattened out upon the upper plane surface of the draw-table. All of the above is substantially the saine as sct forth in the Colburn patents referred to above.

By the present invention, the mechanism described above is somew/liataltered and added to, whereby a lateral stretch is imarted to the glass sheet while on the drawtable. At each edge of the draw-table the outer rows of links, which would comprise the surface whereon the glass sheet is clamped, are replaced by a series of loosely inter ocking links 18, each link 18 being pivoted at its ends on the ad'acent pair of pivot pins or shafts 19, and eing capable of a limited amount of sliding movement lengthwise of these pins. The central links 11 are held a einst sliding movement on the pins by col ars 20. The end portions of each draw-bar 1,5, which rest on the glass sheet, are made in the form of separate extensions 21, each slidable on an extension 22 of the mu'n draw-bar.

Adj iistably mountedron suitable supports, such as the I beams 23, at each side o t the supporting table 12, are guide frames 2l, having flanged extensions 25 and 2G forming upper and lower trackwiiys. 'lhe slida, ble drawvtable links 18, have outwardly projecting portions 27, provided w'ith ro lers or other projections`28,'which travel on the tracks 26, whereas the slidable extensions 21 of the draw-bars have projections 29, provided with rollers 30 or their equiva ent, which travel on t1'acks-25. As shownl in Fig. 3, the tracks 25 and 26 curve outwardly in the direction of travel of the sheet, theV pairs of tracks at the oppositeedgesofthe sheet being further a art at the Adischarge end of the draw mecianisni than they are at the receiving end; The track 25 1s of the .same curvature, and at all points lies directly `above the track 26, so that the rollers 28 and 30,:1ndtlie respective pairs of slidiible sheet gripping members 18 and l21 will at all times move equally and in unison. The positions of the track carrying frames 24, may be adjusted in or out bo Y vary the amount of sliding movement imparted to the gripping members, by means of adjusting screws 31, mounted in ears 32 on the support 23, and screwing into ear extern;V sions 33 on frame 24. If desired the screws 31 can be extended through the sides of the machine frame land provided with suitable hand-wheels 34, as indicated in Fig. 4, so that adjustments can be made from outside of the machine.

Arranged at any suitable point along the idle run of the draw-table is a member 35, 7` (see Fig. 1), carrying an inclined trackivay 3G, which functions to return the links 18 to their initialinward position. A simi lar member 37, having an inclined trackway 38, is mounted above the idle run of 7i the draw-bars to return the extensions 21 to their extreme inner position.

ln operation, the drawn sheet after beine' bent into the horizontal plane and relieated passes into the drawing mechanism where' its edge portions are successively gri ped between the pairs f members v21 an 18. Shortly after each pair of ripping menibers 21 and 18 hafve engaget the sheet, the rollers 30and 28-tliereon are engaged/by 85 the diverging tracks 25 and 26, and .as the endless'drawn'g chains move lforward, the gripping members 21 and 18 are caused to move outwardlyt1ransverse of the glass sheet, tending to, pull the sheet laterally in 9o both directions and stretch the sainecsidewise. As there isla longitudinal pull on the sheet in one direction imparted by the drawing mechanism, and in theotlier direction diie to the viscosit of the molten glass from which the sheet is drawn, racticiilly the entire area of the sheet' resting on. thel draw-tablelwill be'siibjected to u considerable tension' in all directions simultaneously.

rl`his will tend to smooth ont and flatten the 10()` sheet, removing corrugations und wrinkles,` and improving the quality of thil tnislied product. f

It an' lumps* or other foreign substancest should drawn into the glass sheet, mak- 106 'z it of more than normal thickness, the' draw-bars may ride `up over this obstruction, the rollers 3() riding up on, or even passing olf from theI track 25 without damaging the mechanism. lf found desirable, the rollers 110 30 and 28 may be omitted` and simple right-V angled extensions on the members 29 and 27, substituted therefor. These extensions would have a sliding Contact with the tracks 25 and 26. 11i,

I Obviously this invention is not limited to use with the specitir form t diiiiving iiiei'lninisniillustrated. but could be added to aux `forni of drawing mechanism of thil endless belt type.

I claim:

l. ln a sheet glass drawing, apparatus.. means foi' gripping the edges of the sheet. und means Tfor simultaneously moving the gripping moans longitudinally and laterally of the sheet.

2. ln a. sheet glassdrawiiig apparatus. means for sup oi-ting the sheet, mea-ns for gripping thi` sheet edges, to draw the sheet longitudinally, and means for causing the la the sheet and pulling the sheet lengthwise,

and means tor eansing the draw members at each sheet edge to move laterally in the plane of the sheet away from the draw meub v ber at the other sheet edge7 to'simultaneously stretch and flatten the sheet.

4. In an'apparatus for drawing continuous sheet glass, wherein the glass sheet is drawn vertically from a receptacle containing molten glass, bent into the horizontal pla-ne,y and then reheated to soften and flatten the same, a drawing and stretching mechanism. eomprisin an endless carrier or draw-tahle. an end ess series'of clam ing members gripping each edge of t e sheet against the table, means for simultaneously moving the clamping members and table longitudinally of the sheet to draw the same. and means for causing the Clamping members and gri ping portions of the table to more lateral y while gripping the sheet. to stretch the sheet toward its edges.

ln an apparatus for drawing continuons sheet glass, wherein a sheet of glass is drawn from a mass of moltenl glass, mechw nism for drawing the sheet and stretching it laterally1 comprising an endless carrier or draw-table for supporting the sheet, two endless series of clamping membels truvel ing in unison with the ili'a\\'tal lc, one series at vai-h edge ot' the opposite faces of the sheet and gripping the sheet against the edge portions ot the table, the clamping members and gripping portions of the table each being capable of a limited lateral movement and means for causing the two series of clamping membersand gripping portions of the table to simultaneously andin unison move laterally in opposite diret-tions while gripping and drawing the sheet.` thereby inoreasing'the width of the sheet.

In an apparatus t'or drawing continuous sheet glass. wherein a sheetotglass is drawn from a mass of molten glass, mecha.-

nisni for drawing the sheet and stretching it laterally. comprising an endless carrier or draw-table for supporting the sheet, ,two endless series of clamping members traveling in unison with the dra w-table at the opposite face of the sheet. each edge of the sheet being gripped between one series of elemping members and the edge portion of the table. and guide members for causing these sheet gripping devices to -move laterally while engaging the sheet.

T. ln an apparatus for drawing rontinuA ous sheet glass.y wherein a sheet of glass is drawn from a` mass ot' molten glass.` mechanism for drawing the sheet and stretching it laterally. comprising an endless carrier or draw-table for supporting the sheet. two endless series of clamping members tra\-cling in unison with the. draw-tabl(l at thc opposite face ot the sheet. each edge ot' thc sheet being gripped between one series ot Clamping members and the edge portion ol' the table. guide members for causing these sheet gripping devices to more lalcralb while engaging the sheet. and guide mcmhers for returning the gripping devices to their initial position whihl out of cngagemcnt with the sheet.

8. In an apparatus for drawing continu ons sheet glass from a receptacle containing molten glass, four endless series ot' gripping devices. one series engaging nach l'ace` ot' i each edge portion of thc glass sheet. means for moving the devices in unison lengthwisal of the sheet to draw thc sheet from thil molten masirzand means at each edge ot' the sheet for guiding the adjacent pair ot' sheet gripping devices outwardly :Lw-ay from the center line of the sheet while in engagement with the sheet.

9. In an apparatus t'or drawing continu oustsheet glass. gripping means for engaging the opposite faces ot' each edge portion of tiles-heet, means for moving the grippingr means in unison lengthwise ot' the sheet to draw the sheet from its source, and means to simultaneously more the gripping devices laterally at the respective, edges of tlnl sheet. to stretch the sheet laterally.'

lt). In a continuous sheet glass drawing apparatus,. means for gripping the edges of the drawn sheet, means for moving the gripping means longitudinally with the sheet to draw more sheet from the. molten source. and means for simultanwusly moving the gripping means laterally, to stretch that portion ot' the sheet gripped thereby.

11. In :L continuous sheet glass drawing aplmratus,ineans for grip-ping the edges ot' the drawn sheet. means for moving the gripping means longitudinally with the sheet to draw more sheet from the molten source, traveling sheet supporting means moving between and with the two edge gripping' means, and means for simultaneously moving the edge gripping means laterally to 'stretch that portion of the sheet carried by the supportiiw means.

Signed at "oledo, in the county of Lucas and State ot' Ohio, this 29th day ot October. 1920.

CLIFFORD A. ROW LE Y, 

